CN110494479B

CN110494479B - Fluoroelastomer composition

Info

Publication number: CN110494479B
Application number: CN201880021103.2A
Authority: CN
Inventors: S.博索罗; M.阿瓦塔內奧; S.米勒范蒂; M.J.考克斯
Original assignee: Solvay Specialty Polymers Italy SpA
Current assignee: Solvay Specialty Polymers Italy SpA
Priority date: 2017-03-31
Filing date: 2018-03-23
Publication date: 2022-04-15
Anticipated expiration: 2038-03-23
Also published as: CN110494479A; US11851556B2; US11124640B2; JP7088954B2; US20200109273A1; JP2020515670A; EP3601427A1; EP3601427B1; KR20190130145A; WO2018177934A1; KR102552336B1; US20210380793A1

Abstract

The present invention relates to a composition based on a fluoroelastomer comprising nitrile or carboxylate-type cure sites and comprising a curing agent reactive towards said cure sites and a Br-containing tag, which composition can be cured so as to provide a cured part maintaining chemically bonded bromine atoms; thus, such materials, when subjected to wear/damage, will release Br-containing contaminants that can be readily discovered, notably via an online mass spectrometer, in order to monitor and predict critical damage of sealing materials based thereon.

Description

Fluoroelastomer composition

Cross Reference to Related Applications

This application claims priority from european application No. 17164042.8 filed on 31/3/2017, the entire contents of which are incorporated by reference into this application for all purposes.

Technical Field

The present invention relates to a fluoroelastomer composition capable of providing cured parts having the ability to interact with specific sensors in case of wear or damage, to a method of curing the fluoroelastomer composition and to cured articles obtained therefrom, which are notably useful as intelligent seals.

Background

Fluoroelastomers, and more particularly perfluoroelastomers, have long been used in a variety of applications that require resistance to several extreme conditions, including high temperatures, chemical attack, and exposure to plasma, including in particular the semiconductor manufacturing industry. Especially in this field, the possibility of monitoring wear and damage that may be caused in the sealing parts is a necessary requirement for optimizing production, and avoiding waste of off-specification semiconductor articles manufactured due to undesired contaminants or unsuitable manufacturing conditions.

In fact, the seals are mainly made of fluoroelastomers (these fluoroelastomers are in their pure form) and cannot process and/or transmit signals. Several actions are being taken to investigate the original task of enabling the use of a seal as a sensor or a material that can interact with a sensor under specific conditions, without including the seal.

For example, one of the major challenges is to provide a seal that can identify its wear level. This self-monitoring is also referred to as "condition monitoring".

An exemplary solution has been notably described by Freudenberg (see date of annotation 2016, 04, 25, on web pages:https：//www.fst.com/press/2016/freudenberg-smart-sealspress releases available in, downloaded on 3/10/2017); according to this document, a rod seal is provided which is comprised of a conductive elastomer including an effective amount of a conductive filler material and an insulating outer layer, wherein the outer layer is a sealing lip in the seal. When the circuit connects the rod and the housing wall, electricity can become a measurable variable. As the stem seal moves back and forth, the seal lip wears. If the conductive base material reaches the surface, the circuit between the rod and the housing is closed, which is a condition that the LED can signal.

Nevertheless, this solution requires the use of peripheral devices (circuits) in direct contact with the seal to be monitored, which may be an impractical solution in several components.

Thus, there remains a continuing search in this field for curable fluoroelastomer compositions capable of providing cured parts that represent condition monitoring for wear/structural damage, maintain manufacturing costs at reasonable levels, and do not compromise the primary role of the seal.

Disclosure of Invention

Accordingly, a first object of the present invention is a fluoroelastomer composition [ composition (C) ] comprising:

-at least one fluoroelastomer [ fluoroelastomer (a) ] comprising from 0.1 to 10.0% moles, with respect to the total moles of recurring units of fluoroelastomer (a), of recurring units derived from at least one of:

-a monomer containing a cure site having at least one nitrile group [ monomer (CS-N) ];

-monomers containing a curing site having at least one carbon group [ monomers (CS-C)]The carbon radical is selected from the group consisting of: a carboxyl group-COOH; carboxylate group-COOX_aWherein X is_aIs a monovalent metal or an ammonium group; carboxamide group-CONH₂(ii) a And alkoxycarboxyl-COO-R_HWherein R is_HIs a (fluoro) (hydro) carbon radical, preferably C₁-C₃An alkyl group;

-at least one curing agent [ agent (a) ];

-at least one bromine-containing marker [ marker (B) ] selected from the group consisting of compounds comprising at least one Br atom and at least one group selected from:

(B-1) an aromatic o-diamine group;

(B-2) an aromatic o-amino- (thio) phenolic type group;

(B-3) an amidoxime/amidine/amidrazone group having the formula:

wherein R is_N1is-OH or-H, and R_N2Is H or NH₂And an

(B-4) imidoamidine groups having the formula:

(B-5) an azide group having the formula: - (SO)₂)_xn-N₃Wherein xn is 0 or 1;

(B-6) has the formula-J^N-C(O)-NH-NH₂The carbazepine group of (a), wherein J^NIs a bond, an ester oxygen-O-group, or an amine-NH-group.

The applicant has surprisingly found that when combining the above curable compound comprising a fluoroelastomer comprising nitrile cure sites, a curing system for the curable compound and a Br-containing reactive label, this compound can be cured so as to provide a cured part maintaining chemically bonded bromine atoms: thus, such materials, when subjected to wear/damage, will release Br-containing contaminants that originate only from the damage of the seal, since bromine atoms are generally absolutely not contained in the semiconductor raw material or the final part, and these contaminants can be found easily, notably via an online mass spectrometer (such as those conventionally connected to semiconductor manufacturing).

Detailed Description

The composition (C) comprises one or more than one agent (a) as detailed above.

Said agent (A) is an agent capable of promoting the crosslinking of the fluoroelastomer (A) by reaction with the curing sites of the monomers (CS-N) and/or (CS-C) as described above. The reagent (a) may notably be a compound having a plurality of groups reactive towards the nitrile groups and/or carbon groups of the monomers (CS-N) and/or (CS-C) as described above, and/or may be a compound which catalytically activates the same nitrile groups and/or carbon groups of the monomers (CS-N) and/or (CS-C) to react with each other.

The choice of curing agent (a) is not particularly limited and one of ordinary skill in the art will select the most suitable curing agent (a) depending on the nature of the cure site of fluoroelastomer (a).

One or more than one agent (a) may be used in the composition of the invention. Notably, the one or more than one reagent (a) may be chosen from those having groups reactive towards the nitrile and/or carbon groups of the monomers (CS-N) and/or (CS-C) as described above; and one or more than one reagent (a) may be chosen from those that catalytically activate the same nitrile and/or carbon groups of the monomers (CS-N) and/or (CS-C) to react with each other, and one or more than one of these two types of reagents (a) may be used alone or in combination in the composition of the invention.

When the agent (A) is chosen to have catalytic activity on the nitrile and/or carbonyl groups of the monomers (CS-N) and/or (CS-C) as described aboveWhen the active compound is converted, the reagent (A) is referred to as reagent (A)_cat) And may notably be selected from the group consisting of:

organic ammonia-generating compounds, that is to say compounds capable of generating ammonia upon heating (for example under conditions such as those encountered during curing/post-curing);

organotin compounds, such as notably allyl-, propargyl-, triphenyl-, and allenyl-tin curing agents, of which tetraalkyl or tetraaryltin compounds are preferred.

Reagent (A)_cat) Preferably selected from the group consisting of:

(A_cat-1): (thio) urea compounds having the formula (U):

(U)

wherein E is O or S, preferably E is O, and each R_uThe same or different from each other, independently selected from the group consisting of: hydrogen and C₁-C₆Hydrocarbyl (especially C)₁-C₆Alkyl groups);

(A_cat-2): cycloaddition products of ammonia or primary amines with aldehydes;

(A_cat-3): (thio) carbamates of formula (C):

(C) wherein E is oxygen or sulfur; r_bIs C₁-C₃₆A hydrocarbon group, and Rc is H or C₁-C₆An alkyl group;

(A_cat-4): ammonium salts of organic and inorganic acids, notably selected from the group consisting of: (j) ammonium (preferably fluorine-containing) carboxylates; (jj) ammonium (preferably fluorine-containing) sulfonates; (jjj) ammonium (preferably fluoroalkyl containing) phosphates, phosphonates or sulfonates; (jv) ammonium salts of sulfuric acid, carbonic acid, nitric acid and phosphoric acid.

In a suitable reagent (A)_cat) Among them:

(A_cat-1): the (thio) urea compounds as detailed above are preferably selected from the group consisting of (A)_cat-1-a) a group consisting of (thio) ureas having formula (U-2):

(U2) wherein E' is O or S;

(A_cat-2): the cycloaddition product of ammonia or a primary amine with an aldehyde as detailed above is preferably selected from the group consisting of:

(A_cat-2-a) a cyclic aldehyde adduct trimer having the formula (T):

(T) wherein each R_aAre identical or different from each other and are selected from hydrogen and C₁-C₆Hydrocarbyl (especially C)₁-C₆Alkyl) groups;

(A_cat-2-B) hexamethylenetetramine having the formula:

(which is known to be the result of the addition of ammonia to formaldehyde);

(A_cat-3): the (thio) carbamates as detailed above are preferably selected from the group consisting of (A)_cat-3-a) a group consisting of carbamates of formula (C-1):

(C-1) wherein R'_dIs C₁-C₃₆Hydrocarbyl, preferably optionally substituted benzyl.

It has been found that an agent (A) particularly useful in the compositions of the invention_cat) Is the following:

(A_cat-1) a urea having the formula:

it is a preferred choice in terms of cost/availability/reactivity;

(A_cat-2) an acetaldehyde ammonia trimer having the formula:

(A_cat-3) hexamethylenetetramine having the formula:

(A_cat-4) benzyl carbamate having the formula:

when the reagent (A) is selected from compounds having a plurality of groups reactive with the nitrile group and/or the carbon group of the monomer (CS-N) and/or (CS-C) as described above, the reagent (A) is referred to as the reagent (A)_func) And may notably be selected from the group consisting of:

(A_func-1) bis-amino (thio) phenol compounds having the formula [ Aminophenols (AP)]：

Wherein:

-A is a bond, -SO₂-, -O-, -C (O) -or (fluoro) alkyl having 1 to 10 carbon atoms (in particular perfluoroalkyl having 1 to 10 carbon atoms, for example-C (CF)₃)₂-)；

-each E, equal or different at each occurrence, is oxygen or sulfur, preferably oxygen, and wherein the amino group and the-EH group are interchangeably in ortho, meta or para positions relative to the group a;

(A_func-2) an aromatic tetraamine compound having the formula [ amine (TA)]：

Wherein:

-A' is a bond, -SO₂-, -O-, -C (O) -a (fluoro) alkyl group having 1 to 10 carbon atoms (in particular a perfluoroalkyl group having 1 to 10 carbon atoms,for example-C (CF)₃)₂-)；

Each R_NAre, equal to or different from each other, a hydrogen atom or C₁-C₁₂Hydrocarbyl, preferably aryl; and is

-the amino groups are interchangeably in ortho, meta or para position relative to the group A',

-(A_func-3) bisamidoxime/bisamidine/bisaminohydrazone compounds having the formula:

wherein R is_a1is-OH or-H, and R_a2Is H or NH₂And E is C₁-C₁₈A divalent group, optionally comprising a fluorine atom;

-(A_func-4) bisiminoamidine compounds of formula:

wherein E^bIs C₁-C₁₈A divalent group, optionally containing a fluorine atom, and R^bIs C₁-C₁₂The group is optionally fluorinated.

Bisamidoxime/bisamidine/bisaminohydrazone compound (A) as described in detail above_funcAmong-3), mention may notably be made of:

(A_func-3-a): a fluorinated bisamidoxime compound having the formula:

wherein Rf is a divalent fluorinated alkylene, preferably of the formula- (CF)₂)_n-wherein n is 1 to 10, or wherein R_fIs (per) fluoroalkoxyalkylene, preferably selected from- (CFX)_p(OCF₂CFX)_n(OCFX)_mO-(CFX)_p-wherein X is F or-CF 3; n, m are zero or integers, provided that n + m is from 1 to 100; and m is 1 or 2.

(A_func-3-B) an aromatic bisamidoxime compound having the formula:

wherein J^aIs a bond, -SO₂-, -O-, -C (O) -alkyl (fluoro) having 1 to 10 carbon atoms, in particular perfluoroalkyl having 1 to 10 carbon atoms, for example-C (CF)₃)₂-)；

(A_func-3-C): a fluorinated bisaminohydrazone compound having the formula:

wherein R is_fIs a divalent fluorinated alkylene radical, preferably of the formula- (CF)₂)_n-wherein n is 1 to 10, or wherein R_fIs (per) fluoroalkoxyalkylene, preferably selected from- (CFX)_p(OCF₂CFX)_n(OCFX)_mO-(CFX)_p-wherein X is F or-CF 3; n, m are zero or integers, provided that n + m is from 1 to 100; and m is 1 or 2.

(A_func-3-D) an aromatic bisaminohydrazone compound having the formula:

wherein J^cIs a bond, -SO₂-, -O-, -C (O) -alkyl (fluoro) having 1 to 10 carbon atoms, in particular perfluoroalkyl having 1 to 10 carbon atoms, for example-C (CF)₃)₂-)。

According to certain preferred embodiments, the agent (a) is an Aminophenol (AP) as detailed above.

The Aminophenol (AP) may be selected from the group consisting of: 4, 4' - [2,2, 2-trifluoro-1- (trifluoromethyl) -ethylene ] bis (2-aminophenol); 4, 4' -sulfonylbis (2-aminophenol); 3, 3 ' -diaminobenzidine, 3, 3 ', 4,4 ' -tetraaminobenzophenone.

Particularly preferred Aminophenols (AP) are 4, 4' - [2,2, 2-trifluoro-1- (trifluoromethyl) -ethylene]Bis (2-aminophenol), otherwise known as bisaminophenol AF, havingHaving the formula:

the composition (C) comprises one or more than one marker (B) as detailed above.

Without being bound by this theory, the applicant has surprisingly found that the marker (B) as detailed above has the ability to react with the fluoroelastomer (a) as detailed above without undergoing any significant evaporation loss or decomposition during moulding, curing and post-curing, thus ensuring the presence of bromine atoms in the final rubber part moulded from the composition of the invention, which can be easily detected by different analytical techniques (notably including mass spectrometry) if and when released in certain environments (for example due to wear and/or material decomposition, whatever the cause).

This is particularly advantageous in particular in semiconductor manufacturing, where fluoroelastomers are widely used as sealing materials, and where, from the one hand, conditions are extremely harsh and demanding, including for example plasma radiation, HF and other etching gas exposures, and also where extreme cleanliness and the absence of any type of contamination, including waste of damaged equipment's seals, is mandatory to meet quality standards.

As mentioned above, the label (B) comprises at least one bromine atom. The label (B) may comprise one or more than one bromine atom.

Typically, the label (B) (wherein at least one bromine atom is bonded to sp) as detailed above²-on a hybrid aromatic carbon) is preferred. In fact, in the marker (B), at least one bromine atom passes to the cyclic aromatic sp²Said bonds on the hybridized carbons are bonded to aromatic moieties, enhancing the thermal resistance of said Br-C bonds, so as to intervene mainly and substantially on the bromine release from composition (C) and/or from the cured parts derived therefrom, due to the critical destruction of composition (C) and/or of the cured parts derived therefrom.

As mentioned above, composition (C) comprises one or more than one reagent (a) as detailed above and one or more than one label (B) comprising at least one Br atom and at least one group of (B-1) to (B-6) as detailed above.

Those skilled in the art recognize that the groups (B-1) to (B-6) as detailed above are groups capable of reacting with the nitrile or carbon groups of the fluoroelastomer (A); thus, for embodiments in which label (B) comprises more than one (e.g., two, or three, or more) group of the types (B-1) to (B-6), label (B) may actually be reagent (A), and more specifically reagent (A)_func) Are suitable, as detailed above.

Thus, although the invention encompasses embodiments in which reagent (A) and label (B) are different compounds, it is not inconsistent with embodiments using labels (B) having more than one group of the type (B-1) to (B-6) in combination with reagent (A) that is not different from label (B).

When the reagent (a) is different from the marker (B), the composition (C) comprises:

-a marker (B) as detailed above, in an amount generally ranging from 0.10 to 10phr, preferably from 0.25 to 5phr, with respect to the fluoroelastomer (a); and

-an agent (a) as detailed above, in an amount ranging from 0.10 to 10phr, preferably from 0.25 to 5phr, with respect to the fluoroelastomer (a).

When marker (B) is a compound having more than one group of the type (B-1) to (B-6) and is suitable both as marker (B) and as agent (A) in composition (C), its amount ranges overall from 0.20 to 10phr, preferably from 0.3 to 6phr, with respect to fluoroelastomer (A).

With respect to the label (B-1) as detailed above, the expression "aromatic ortho-diamine group" is used to denote a group comprising an aromatic ring (which may or may not be condensed into another aromatic or non-aromatic ring, which may or may not carry substituents other than amine groups, and which may be an aromatic heterocyclic ring or may not contain cyclic atoms other than carbon) having two cyclic aromatic sp's directly bonded to one in ortho-position with respect to the other²Two amine groups on hybridized carbon。

Among the labels containing (B-1) aromatic ortho-diamine groups, particularly preferred are compounds containing ortho-diamine phenyl groups having the following formula (B-1-a):

among these markers (B-1), particularly useful compounds are notably those of the formula:

-(B-1-i)

-(B-1-ii)

and

-(B-1-iii)

compounds which have been found to be particularly effective are compounds having the formula (B-1-iv):

similarly, with respect to the label (B-2) as detailed above, the expression "aromatic ortho amino- (thio) phenol-type group" is used to denote a group comprising an aromatic ring (which may or may not be condensed into another aromatic or non-aromatic ring, which may or may not carry substituents other than amine and hydroxyl groups, and which may be an aromatic heterocycle or may not contain cyclic atoms other than carbon) having two cyclic aromatic sp's directly bonded to one in ortho-position with respect to the other²Amine and hydroxyl groups on the hybridized carbon.

Among the markers containing (B-2) aromatic o-amino- (thio) phenol-type groups, those containing a compound having the formula (B-2-a)The amino- (thio) phenol group of (a):

wherein E^mIs O or S.

Among these markers (B-2), particularly useful compounds are notably those of the formula:

-(B-2-i)

-(B-2-ii)

-(B-2-iii)

compounds of the (B-2) -type which have been found to be particularly effective are compounds having the formulae (B-2-iv) and (B-2-v):

wherein E^mIs O or S; and more specifically compounds having the formulae (B-2-vi) and (B-2-vii):

comprising an amidoxime/amidine/amidrazone group having the formula:

(wherein R is_N1is-OH or-H, and R_N2Is H or NH₂) The marker (B-3) of (A) is generally selected from the group consisting of: a compound comprising a group having the formula:

and compounds comprising a group of the formula：

Compounds of the (B-3) -type which have been found to be particularly effective are compounds having the formula:

-(B-3-i)

-(B-3-ii)

-(B-3-iii)

wherein the symbols relating to aromatic rings

It is intended to mean that all free valences of the aromatic ring are substituted by fluorine atoms;

-(B-3-iv)

wherein the symbols relating to aromatic rings

It is intended to mean that all free valences of the aromatic ring are substituted by fluorine atoms.

Comprising imidoamidine groups having the formula:

the marker (B-4) of (A) is generally selected from the group consisting of:

-(B-4-i)

wherein Ar is^IMIs an aromatic group, possibly fluorinated; j. the design is a square^IMIs C₁-C₁₈Divalent radicals, possibly fluorinated, possibly containing ether oxygen atomsFor example, like a fluoroalkoxyalkylene chain; n is_IMIs an integer from 1 to 4;

-(B-4-ii)

wherein R is^IMIs C₁-C₁₂A group, possibly fluorinated;

-(B-4-iii)

wherein R is^IMIs C₁-C₁₂The group, possibly fluorinated.

The label (B-5) comprising an azide group as detailed above is generally selected from the group consisting of:

-(B-5-i)

and

-(B-5-ii)

wherein the symbols relating to aromatic rings

Comprises a compound having the formula-J^N-C(O)-NH-NH₂Imide (imine) groups of (wherein J)^NA bond, an ester oxygen-O-group, or an amine-NH-group) is selected from the group consisting of:

-(B-6-i)

wherein n is_YMIs an integer of 1 to 4, Ar^YMIs an aromatic group, possibly fluorinated;

-(B-6-ii)

-(B-6-iii)

wherein n is_YMIs an integer of 1 to 4, Ar^YMIs an aromatic group, possibly fluorinated.

Compounds of the (B-6) -type which have been found to be particularly effective are compounds having the formula:

-(B-6-iv)

-(B-6-v)

wherein the symbols relating to aromatic rings

-(B-6-vi)

and

-(B-6-vii)

wherein the symbols relating to aromatic rings

The composition (C) comprises one or more than one fluoroelastomer (a) as detailed above.

For the purposes of the present invention, the term "(per) fluoroelastomer" [ fluoroelastomer (a) ] is intended to denote a fluoropolymer resin used as a base ingredient for obtaining a true elastomer, said fluoropolymer resin comprising more than 10% by weight, preferably more than 30% by weight, of recurring units derived from at least one ethylenically unsaturated monomer containing at least one fluorine atom (hereinafter, (per) fluorinated monomer) and optionally recurring units derived from at least one ethylenically unsaturated monomer free from fluorine atoms (hereinafter, hydrogenated monomer).

True elastomers are defined by ASTM, Special Technical Bulletin, standard No.184 (Special Technical Bulletin, No.184 standard) as materials that can be stretched to twice their natural length at room temperature and recover within 10% of their original length within the same time once they are released after being held under tension for 5 minutes.

In general, fluoroelastomer (a) comprises, in addition to recurring units derived from monomers (CS-N) and/or (CS-C) as detailed above, recurring units derived from at least one (per) fluorinated monomer, wherein said (per) fluorinated monomer is generally selected from the group consisting of:

-C₂-C₈fluoro-and/or perfluoroolefins, such as Tetrafluoroethylene (TFE), Hexafluoropropylene (HFP), pentafluoropropene, and hexafluoroisobutylene;

-C₂-C₈hydrogenated monofluoroolefins, such as vinyl fluoride;

1, 2-difluoroethylene, vinylidene fluoride (VDF) and trifluoroethylene (TrFE);

-corresponds to the formula CH₂＝CH-R_f0Of (per) fluoroalkylethylenes of (a), wherein R_f0Is C₁-C₆(per) fluoroalkyl or C with one or more ether groups₁-C₆(per) fluorooxyalkyl;

-chloro-and/or bromo-and/or iodo-C₂-C₆Fluoroolefins like Chlorotrifluoroethylene (CTFE);

-corresponds to the formula CF₂＝CFOR_f1Fluoroalkyl vinyl ether of (2), wherein R_f1Is C₁-C₆Fluoro-or perfluoroalkyl, e.g. -CF₃、-C₂F₅、-C₃F₇；

-corresponds to the formula CH₂＝CFOR_f1In which R is_f1Is C₁-C₆Fluoro-or perfluoroalkyl radicals, e.g.Such as-CF₃、-C₂F₅、-C₃F₇；

-corresponds to the formula CF₂＝CFOX₀In which X is₀Is C₁-C₁₂An oxyalkyl group, or C having one or more ether groups₁-C₁₂(per) fluorooxyalkyl; in particular according to the formula CF₂＝CFOCF₂OR_f2Of (per) fluoro-methoxy-vinyl ether of (meth), wherein R_f2Is C₁-C_aFluoro-or perfluoroalkyl, e.g. -CF₃、-C₂F₅、-C₃F₇Or C having one or more ether groups₁-C₆(per) fluorooxyalkyl, like-C₂F₅-O-CF₃；

-corresponds to the formula CF₂＝CFOY₀Functional fluoro-alkyl vinyl ethers of (a), wherein Y₀Is C₁-C₁₂Alkyl or (per) fluoroalkyl, or C₁-C₁₂Oxyalkyl or C₁-C₁₂(per) fluorooxyalkyl, said Y₀The groups comprise carboxylic or sulfonic acid groups in their acid, acid halide or salt form;

-a (per) fluorodioxole having the formula:

wherein R is_f3、R_f4、R_f5、R_f6Each of which is the same as or different from each other, independently a fluorine atom, C₁-C₆Fluoro-or per (halo) fluoroalkyl optionally containing one or more oxygen atoms, e.g. -CF₃、-C₂F₅、-C₃F₇、-OCF₃、-OCF₂CF₂OCF₃。

Examples of hydrogenated monomers are notably hydrogenated alpha-olefins, including ethylene, propylene, 1-butene, diene monomers, styrene monomers, typically alpha-olefins are used.

The fluoroelastomers (A) are overall amorphous products or have a low crystallinity (crystalline phase by volume)Less than 20%) and a glass transition temperature (T) below room temperature_g) The product of (1). In most cases, the fluoroelastomer (A) advantageously has a T of less than 10 ℃, preferably less than 5 ℃, more preferably 0 ℃_g。

The fluoroelastomer (a) is preferably selected from:

(1) VDF-based copolymers wherein VDF is copolymerized with monomers (CS-N) and/or monomers (CS-C) as detailed above and at least one further comonomer selected from the group consisting of:

(a)C₂-C₈perfluoroolefins, such as Tetrafluoroethylene (TFE), Hexafluoropropylene (HFP);

(b) containing hydrogen C₂-C₈Olefins, such as Vinyl Fluoride (VF), trifluoroethylene (TrFE), Hexafluoroisobutylene (HFIB), of formula CH₂＝CH-R_fWherein R is_fIs C₁-C₆A perfluoroalkyl group;

(c) c comprising at least one of iodine, chlorine and bromine₂-C₈Fluoroolefins, such as Chlorotrifluoroethylene (CTFE);

(d) having the formula CF₂＝CFOR_f(per) fluoroalkyl vinyl ethers (PAVE) of (a), wherein R_fIs C₁-C₆(per) fluoroalkyl, preferably CF₃、C₂F₅、C₃F₇；

(e) Having the formula CF₂(per) fluoro-oxy-alkyl vinyl ethers of CFOX, wherein X is C containing catenary oxygen atoms₁-C₁₂((per) fluoro) -oxyalkyl, such as perfluoro-2-propoxypropyl;

(f) (per) fluorodioxoles having the formula:

wherein R is_f3、R_f4、R_f5、R_f6Each of which is the same or different from each other, is independently selected from the group consisting of: fluorine atom and C optionally containing one or more than one oxygen atom₁-C₆(per) fluoroalkyl groups, notably like-CF₃、-C₂F₅、-C₃F₇、-OCF₃、-OCF₂CF₂OCF₃(ii) a Preferably, perfluorodioxoles;

(g) (per) fluoro-methoxy-vinyl ether (MOVE, herein after) having the formula:

CF₂＝CFOCF₂OR_f2

wherein R is_f2Selected from the group consisting of: c₁-C₆(per) fluoroalkyl; c₅-C₆A cyclic (per) fluoroalkyl group; and C containing at least one catenary oxygen atom₂-C₆(per) fluorooxyalkyl; r_f2Preferably is-CF₂CF₃(MOVE1)；-CF₂CF₂OCF₃(MOVE 2); or-CF₃(MOVE3)；

(h)C₂-C₈Non-fluorinated olefins (O1), such as ethylene and propylene; and

(2) TFE-based copolymers, wherein TFE is copolymerized with a monomer (CS-N) and/or a monomer (CS-C) as detailed above and at least one additional comonomer selected from the group consisting of: (c), (d), (e), (g), (h) and (i) as detailed above.

Fluoroelastomer (a) generally selected from TFE-based copolymers as detailed above.

Optionally, the fluoroelastomer (a) OF the invention may also comprise recurring units derived from a bis-olefin [ bis-Olefin (OF) ] having the general formula:

wherein R is₁、R₂、R₃、R₄、R₅And R₆Are identical or different from each other and are H or C₁-C₅An alkyl group; z is a linear or branched C optionally containing oxygen atoms, preferably at least partially fluorinated₁-C₁₈(hydro) carbon groups (including alkylene or cycloalkylene groups)) Or a (per) fluoro (poly) oxyalkylene group containing one or more catenary ether linkages.

The bis-Olefin (OF) is preferably selected from the group consisting OF: those complying with formulae (OF-1), (OF-2) and (OF-3):

(OF-1)

wherein j is an integer between 2 and 10, preferably between 4 and 8, and R1, R2, R3, R4, equal to or different from each other, are H, F or C_1-5Alkyl or (per) fluoroalkyl;

(OF-2)

wherein each a, the same or different from each other and at each occurrence, is independently selected from F, Cl and H; each B is the same OR different from each other and, at each occurrence, is independently selected from F, Cl, H, and OR_BWherein R is_BIs a branched or straight chain alkyl group which may be partially, substantially or fully fluorinated or chlorinated; e is an optionally fluorinated divalent group having 2 to 10 carbon atoms, which may be interrupted by ether linkages; preferably E is- (CF)₂)_m-a group, wherein m is an integer from 3 to 5; a preferred bis-olefin OF the type (OF-2) is F₂C＝CF-O-(CF₂)₅-O-CF＝CF₂。

(OF-3)

Wherein E, A and B have the same meaning as defined above; r5, R6 and R7 are the same or different and are H, F or C_1-5Alkyl or (per) fluoroalkyl.

Among the monomers containing a curing site of the type (CS-N) contained in fluoroelastomer (a) as detailed above, preferred monomers are (per) fluorinated and in particular those selected from the group consisting of:

(CS-N1) has the formula CF₂＝CF-(OCF₂CFX^CN)_m-O-(CF₂)_n-CN nitrile group-containing perfluorovinyl ethers of which X is^CNIs F or CF₃M is 0, 1, 2, 3 or 4; n is an integer from 1 to 12;

(CS-N2) has the formula CF₂＝CF-(OCF₂CFX^CN)_m，-O-CF₂-CF(CF₃) -CN nitrile group-containing perfluorovinyl ethers of which X is^CNIs F or CF₃And m' is 0, 1, 2, 3 or 4.

Specific examples of monomers containing a curing site of the type CS-N1 and CS-N2 suitable for the purposes of the present invention are notably those described in patents US 4281092 (DUPONT) 28/07/1981, US 4281092 (DUPONT) 28/07/1981, US 5447993 (DUPONT) 5/09/1995 and US 5789489 (DUPONT) 4/08/1998.

A preferred cure site monomer (CS-N) is perfluoro (8-cyano-5-methyl-3, 6-dioxa-1-octene) having the formula: CF (compact flash)₂＝CF-O-CF₂-CF(CF₃)-O-CF₂-CF₂-CN(8-CNVE)。

Among the monomers containing a curing site of the type (CS-C) contained in fluoroelastomer (a) as detailed above, the preferred monomers are (per) fluorinated and in particular those selected from the group consisting of:

(CS-C1) has the formula CF₂＝CF-(OCF₂CFX^C)_m-O-(CF₂)_n-R_COXContaining a carbon group, wherein X is^CIs F or CF₃M is 0, 1, 2, 3 or 4; n is an integer from 1 to 12, and R_COXSelected from the group consisting of: a carboxyl group-COOH; carboxylate group-COOX_aWherein X is_aIs a monovalent metal or an ammonium group; carboxamide group-CONH₂(ii) a And alkoxycarboxyl-COO-R_HWherein R is_HIs a (fluoro) (hydro) carbon radical, preferably C₁-C₃An alkyl group;

(CS-C2) has the formula CF₂＝CF-(OCF₂CFX^C)_m’-O-CF₂-CF(CF₃)-R_COXWherein m' is 0, 1, 2, 3 or 4, and X is^CAnd R_COXHave the meaning as defined for (CSC-1).

However, it is generally preferred that the fluoroelastomer (a) comprises repeating units derived from monomers containing a cure site, of the type (CS-N) as detailed above, i.e. a fluoroelastomer (a) that is a nitrile curable compound.

Exemplary preferred fluoroelastomers (a) useful in the compositions of the present invention are those having the following monomer composition (in mol%, relative to the total moles of recurring units):

(i) tetrafluoroethylene (TFE): 50% -80%; (per) fluoroalkyl vinyl ether (PAVE): 15% -50%; monomer (CS-N): 0.1% -10%; bis-Olefins (OF): 0% -5%;

(ii) tetrafluoroethylene (TFE): 20% -70%; (per) fluoro-methoxy-vinyl ether (MOVE): 25% -75%; (per) fluoroalkyl vinyl ether (PAVE): 0% -50%; 0.1 to 10 percent of monomer (CS-N); bis-Olefins (OF): 0 to 5 percent.

The composition (C) may further comprise further ingredients which may be conventionally used for curing fluoroelastomers; more specifically, the composition (C) may usually further comprise

(a) One or more than one metal basic compound in an amount generally from 0.5 to 15phr, and preferably from 1 to 10phr, with respect to 100 parts by weight of fluoroelastomer (a); the metal base compound is generally selected from the group consisting of: (j) oxides or hydroxides of divalent metals, such as Mg, Zn, Ca or Pb, and (jj) metal salts of weak acids, such as stearates, benzoates, carbonates, oxalates or phosphites of Ba, Na, K, Pb, Ca;

(b) one or more than one acid acceptor which is not a metal basic compound, in an amount generally from 0.5 to 15phr, and preferably from 1 to 10phr, relative to 100 parts by weight of fluoroelastomer (a); these acid acceptors are generally selected from nitrogen-containing organic compounds, such as 1, 8-bis (dimethylamino) naphthalene, octadecylamine, etc., as notably described in EP 708797 a (dupont) 1/05/1996;

(c) other conventional additives such as fillers, thickeners, pigments, antioxidants, stabilizers, processing aids, and the like.

Among the fillers, fluorinated reinforcing fillers, in particular of nanometric size, consisting of fluoroplastics, can be advantageously used. Thus, according to certain embodiments, the composition of the invention may comprise, with respect to 100 parts by weight of fluoroelastomer (a), generally at least one semi-crystalline fluoropolymer in an amount of from 10 to 70 parts by weight, preferably from 12 to 60 parts by weight; the semi-crystalline fluoropolymer is generally selected from the group consisting of: tetrafluoroethylene (TFE) homopolymers and copolymers of TFE with one or more monomers containing at least one unsaturation of ethylene type, in amounts from 0.01 to 10 mol% and preferably from 0.05 to 7 mol%. Within this framework, it is particularly preferred to include a copolymer derived from at least one compound having the formula CF₂＝CFOR_f(per) fluoroalkyl vinyl ether (PAVE) (where R is_fIs C₁-C₆(per) fluoroalkyl, preferably CF₃、C₂F₅、C₃F₇) A semi-crystalline TFE copolymer of (1). From a morphological point of view, preferred semi-crystalline fluoropolymers for these embodiments are those having an average particle size between 10 and 400nm, preferably 10 to 250nm, even more preferably 10 to 100 nm.

The invention also relates to a process for the manufacture of a shaped article, which comprises curing the composition (C) as described above.

The composition (C) can be manufactured, for example, by molding (injection molding, extrusion molding), calendering, or extrusion into the desired shaped article, which is advantageously subjected to vulcanization (curing) during processing itself and/or in a subsequent step (post-treatment or post-curing); the relatively soft, weak, fluoroelastomer uncured composition is advantageously converted into a finished article made from a non-tacky, strong, insoluble, chemical and heat resistant cured fluoroelastomer material.

However, the present invention relates to the cured articles obtained from the composition (C) as detailed above. The cured article is typically obtained by molding and curing the fluoroelastomer composition as detailed above. These cured articles may be sealing articles including O (square) -rings, shims, gaskets, spacers (diaphragm), shaft seals, valve stem seals, piston rings, crankshaft seals, camshaft seals, and oil seals, or may be pipes and tubes, particularly flexible hoses or other items, including conduits for the delivery of hydrocarbon fluids and fuels.

Further still, the present invention relates to a process for processing the composition (C) as detailed above according to any of injection moulding, compression moulding, extrusion moulding, coating, screen printing techniques, in-situ forming techniques.

Furthermore, the present invention relates to a method for detecting wear/damage of a cured article as detailed above, said method comprising monitoring the release of bromine-containing compounds resulting from said wear/damage.

The technique for monitoring the release of the bromine-containing compound is not particularly limited and may be based on standard analytical techniques. Mass spectrometry is particularly useful for detecting bromine-containing compounds due to the characteristic double peak associated with ions that have lost a bromine atom.

If the disclosure of any patent, patent application, and publication incorporated by reference herein conflicts with the present description to the extent that no ambiguity in terminology is resolved, then the present description shall prevail.

The present invention will now be described in more detail with reference to the following examples, which are intended to be illustrative only and not to limit the scope of the present invention.

Raw material

Bis-aminophenol AF (BOAP, hereinafter), supplied by Apollo Scientific and used as such.

2-amino-4-bromophenol (ABP, infra) having the formula:

supplied by apollo scientific and used as such.

3-bromobenzylamidine hydrochloride (BBA, infra) of the formula:

supplied by floro chemical company (Fluorochem) and used as such.

3-bromobenzonitrile (BBN, infra) having the formula:

supplied by Sigma Aldrich (Sigma Aldrich) and used as such.

4-bromo-tetrafluorobenzonitrile (BFBN, infra) having the formula:

supplied by apollo scientific and used as such.

Preparation example 1-manufacture of nitrile group containing elastomer

In a 5 liter reactor equipped with a mechanical stirrer operating at 630rpm, 3.11 of demineralized water and 31ml of microemulsion, obtained beforehand by mixing: 7.4ml of a perfluoropolyoxyalkylene having an acidic end group having the formula: CF (compact flash)₂ClO(CF₂-CF(CF₃)O)_n(CF₂O)_mCF₂COOH (where n/m is 10, with a weight average molecular weight of 600), 1.9ml of 30% v/v NH₄Aqueous OH solution, 17.4ml demineralized water and 4.3ml of a solution of the formula

D02 perfluoropolyether:

CF₃O(CF₂CF(CF₃)O)_n(CF₂O)_mCF₃(wherein n/m is 20, having a weight average molecular weight of 450).

Heating and maintaining the reactor at a set point temperature of 80 ℃; a mixture of Tetrafluoroethylene (TFE) (35 mol%) and perfluoromethyl vinyl ether (MVE) (64.3 mol%) and ethane (0.7 mol%, chain transfer agent) was then added to reach a final pressure of 21 bar (2.1 MPa). 0.31g of Ammonium Persulfate (APS) was then introduced as initiator. The pressure was maintained at a set point of 21 bar by continuously feeding a gaseous mixture of TFE (57.5% moles) and MVE (42.5% moles) until a total of 1350g, and 129g of 8-CNVE were fed to the reactor in 20 parts for each 5% increase in conversion, starting from the start of the polymerization. In addition, 0.16g of APS was introduced at 15%, 40% and 55% conversion of the gaseous mixture. The reactor was then cooled, vented, and the latex recovered. The latex was coagulated with nitric acid as coagulant and the polymer was separated from the aqueous phase, washed with demineralized water and dried in a convection oven at 120 ℃ for 24 hours.

From the NMR analysis it was found that the composition of the obtained polymer was: TFE 60.8% mol, MVE 38.0% mol, 8-CNVE 1.2% mol, and Mooney viscosity at 121 ℃ of 50 MU.

Universal compounding and curing procedure

The fluoroelastomer of preparation example 1 was compounded in a two roll open mill with the ingredients as detailed below. The substrates were cured in a pressurized mold and then post-treated in an air circulation oven under the conditions detailed in the table below.

The curing behaviour was characterised by a Moving Die Rheometer (MDR) at 170 ℃ by determining the following characteristics:

M_Lminimum torque (1b x in)

M_HMaximum torque (1b x in)

t_S2From M coking time_LTime (seconds) of two units up;

t₀₂time to 2% cure (seconds);

t₅₀time to 50% cure (seconds);

t₉₀time to 90% cure (seconds);

t₉₅time to reach 95% cure state (seconds).

The tensile properties of the samples punched out of the substrate (after post-curing and after exposure to superheated water vapor at 220 ℃ or 250 ℃) have been determined according to ASTM D412C.

TS is tensile strength in MPa;

M₅₀is the modulus in MPa at 50% elongation;

M₁₀₀is the modulus in MPa at 100% elongation;

e.b. elongation at break in%.

Compression Set (CS) values have been determined according to ASTM D395-B method on O-rings (# grade 214) at temperatures ranging from 200 ℃ to 300 ℃; the values in the table are the average of the measurements made on 4 samples.

For all other working and non-working examples, procedures similar to those described for example 1 above were repeated, the compositions and the characterizing features of these examples being summarized in the following table.

TABLE 1

TABLE 2

Determination of bromine content

After (i) compounding the elastomer with the ingredients listed in table 1, (ii) after curing/molding under the conditions detailed above; (iii) br content was determined by XRF after post-curing at 290 ℃. The results are summarized in the table below.

TABLE 3

The data contained in the table below demonstrate that the presence of a bromine-containing reactive label does not adversely affect the mechanical and sealing properties of the compound containing the bromine-containing reactive label.

TABLE 4

Detection of bromine by mass spectrometry

Samples of examples 2 and 3C were subjected to thermogravimetric analysis, coupled mass spectrometry analysis on-line analysis of off-gas from TGA. At temperatures near 450 ℃, significant intensities associated with pairs of peaks having gaps of 2m/z units between them and nearly equal heights (e.g., at 265 and 267 m/z) were detected for mass spectrometry analysis of the exhaust gas generated by sample example 2, whereas no m/z pairs of this type were found in the same spectral region in the exhaust gas from the TGA of example 3C. This indicates that mass spectrometry can selectively discover critical disruption of the cured material (including bromine labels) by identifying peaks that are characteristic for the presence of bromine.

Claims

1. A fluoroelastomer composition comprising:

-at least one fluoroelastomer comprising from 0.1 to 10.0% moles, with respect to the total moles of recurring units of said fluoroelastomer, of recurring units derived from at least one of:

-a monomer containing a curing site having at least one nitrile group, called monomer (CS-N);

-at least one curing agent;

-at least one bromine-containing label selected from the group consisting of compounds comprising at least one Br atom and at least one group selected from:

(B-1) an aromatic o-diamine group;

(B-2) an aromatic o-amino- (thio) phenolic type group;

(B-3) an amidoxime/amidine/amidrazone group having the formula:

wherein R is_N1is-OH or-H, and R_N2Is H or NH₂And an

(B-4) imidoamidine groups having the formula:

2. Composition according to claim 1, in which the curing agent is chosen from compounds having catalytic activity on the activation of the nitrile groups of the monomer (CS-N) and in which the curing agent is referred to as agent (A)_cat) And is selected from the group consisting of:

-organic ammonia-generating compounds, that is to say compounds capable of generating ammonia when heated;

-organotin compounds.

3. The composition according to claim 2, wherein the organotin compound is an allyl-, propargyl-, triphenyl-, and allenyl-tin curing agent.

4. The composition according to claim 2, wherein the organotin compound is a tetraalkyl or tetraaryltin compound.

5. The composition of claim 2, wherein the organic ammonia-generating compound is a compound capable of generating ammonia under those conditions encountered during curing/post-curing.

6. The composition according to claim 2, wherein the agent (A)_cat) Selected from the group consisting of:

(A_cat-1): (thio) urea compounds having the formula (U):

wherein E is O or S, and each R_uThe same or different from each other, independently selected from the group consisting of: hydrogen and C₁-C₆A hydrocarbyl group;

(A_cat-2): cycloaddition products of ammonia or primary amines with aldehydes;

(A_cat-3): (thio) carbamates of formula (C):

(A_cat-4): ammonium salts of organic and inorganic acids selected from the group consisting of: (j) an ammonium carboxylate; (jj) ammonium sulfonate; (jjjj) an ammonium phosphate, phosphonate, or sulfonate; (jv) ammonium salts of sulfuric acid, carbonic acid, nitric acid and phosphoric acid.

7. The composition of claim 6, wherein in formula (U), E is O.

8. The composition of claim 6 wherein said (j) ammonium carboxylate salt contains fluorine.

9. The composition of claim 6 wherein the (jj) ammonium sulfonate salt contains fluorine.

10. The composition of claim 6 wherein the (jjj) ammonium phosphate, phosphonate or sulfonate fluoroalkyl group.

11. The composition of claim 6, wherein in formula (U), each R is_uIndependently selected from C₁-C₆An alkyl group.

12. The composition of claim 6, wherein agent (A)_cat) Selected from the group consisting of:

(A_cat-1): the (thio) urea compound is selected from the group consisting of (A)_cat-1-a) a group consisting of (thio) ureas having formula (U-2):

(U2) wherein E' is O or S;

(A_cat-2): the cycloaddition product of ammonia or a primary amine with an aldehyde is selected from the group consisting of:

(A_cat-2-a) a cyclic aldehyde adduct trimer having the formula (T):

(T) wherein each R_aIdentical or different from each other, selected from the group consisting of: hydrogen and C₁-C₆A hydrocarbyl group;

(A_cat-2-B) hexamethylenetetramine having the formula:

which is known to be the result of the addition of ammonia to formaldehyde;

(A_cat-3): the (thio) carbamate is selected from the group consisting of (A)_cat-3-a) a group consisting of carbamates of formula (C-1):

(C-1) wherein R'_dIs C₁-C₃₆A hydrocarbyl group.

13. The composition of claim 12, wherein R'_dIs an optionally substituted benzyl group.

14. The composition of claim 12, wherein R_aIs selected from C₁-C₆An alkyl group.

15. Composition according to claim 1, in which the curing agent is chosen from compounds having groups reactive with the nitrile groups of the monomer (CS-N) and in which the curing agent is referred to as agent (A)_func) And is selected from the group consisting of:

(A_func-1) a bis-amino (thio) phenol compound having the formula:

wherein:

-A is a bond, -SO₂-, -O-, -C (O) -or a (fluoro) alkyl group having 1 to 10 carbon atoms;

-each E, the same or different at each occurrence, is oxygen or sulfur, and wherein the amino group and-EH group are interchangeably ortho, meta or para with respect to the group a;

(A_func-2) an aromatic tetraamine compound having the formula:

wherein:

-A' is a bond, -SO₂-, -O-, -C (O) -a (fluoro) alkyl group having 1 to 10 carbon atoms;

each R_NAre, equal to or different from each other, a hydrogen atom or C₁-C₁₂A hydrocarbyl group; and is

wherein R is_a1is-OH or-H; and R is_a2Is H or NH₂(ii) a And E is C₁-C₁₈A divalent group, optionally comprising a fluorine atom;

-(A_func-4) bisiminoamidine compounds of formula:

wherein E^bIs C₁-C₁₈A divalent group, optionally comprising a fluorine atom; and R is^bIs C₁-C₁₂The group is optionally fluorinated.

16. The composition of claim 15, wherein E is oxygen.

17. The composition of claim 15, wherein R_NIs an aryl group.

18. The composition of claim 15, wherein a is perfluoroalkyl having 1 to 10 carbon atoms.

19. The composition of claim 15, wherein a is-C (CF)₃)₂-。

20. The composition of claim 15, wherein a' is a perfluoroalkyl group having 1 to 10 carbon atoms.

21. The composition of claim 15, wherein a' is-C (CF)₃)₂-。

22. The composition according to claim 15, wherein the agent (A)_func) Is 4, 4' - [2,2, 2-trifluoro-1- (trifluoromethyl) -ethylene]Bis (2-aminophenol), otherwise known as bisaminophenol AF, has the formula:

23. the composition according to any one of claims 1 to 22, wherein the bromine-containing marker is a marker (B-1) comprising at least one aromatic ortho-diamine group and is selected from the group consisting of:

-(B-1-i)

-(B-1-ii)

and

-(B-1-iii)

24. the composition of any one of claims 1 to 22, wherein the bromine-containing marker is a marker (B-2) comprising at least one aromatic ortho-amino- (thio) phenol-type group and is selected from the group consisting of compounds having the formula:

-(B-2-i)

-(B-2-ii)

-(B-2-iii)

wherein E^mIs O or S.

25. The composition of any one of claims 1 to 22, wherein the bromine-containing label is label (B-3) comprising an amidoxime/amidine/amidrazone group having the formula:

wherein R is_N1is-OH or-H, and R_N2Is H or NH₂And is selected from the group consisting of compounds having the formula:

-(B-3-i)

-(B-3-ii)

-(B-3-iii)

wherein the symbols relating to the aromatic rings

-(B-3-iv)

wherein the symbols relating to the aromatic rings

26. The composition of any one of claims 1 to 22, wherein the bromine-containing label is label (B-4) comprising at least one imidoamidine group having the formula:

and is selected from the group consisting of:

-(B-4-i)

wherein Ar is^IMIs an aromatic group; j. the design is a square^IMIs C₁-C₁₈A divalent group; n is_IMIs an integer from 1 to 4;

-(B-4-ii)

wherein R is^IMIs C₁-C₁₂A group;

-(B-4-iii)

wherein R is^IMIs C₁-C₁₂A group.

27. The composition of claim 26, wherein J^IMIs fluorinated.

28. The composition of claim 26, wherein J^IMContaining an ether oxygen atom.

29. The composition of claim 26, wherein J^IMComprising a fluoroalkoxyalkylene chain.

30. The composition of claim 26, wherein Ar^IMIs fluorinated.

31. The composition of claim 26, wherein in formula (B-4-ii), R^IMIs fluorinated.

32. The composition of claim 26, wherein in formula (B-4-iii), R^IMIs fluorinated.

33. The composition of any one of claims 1 to 22, wherein the bromine-containing label is a label (B-5) comprising at least one azide group and is selected from the group consisting of:

-(B-5-i)

and

-(B-5-ii)

wherein the symbols relating to the aromatic rings

34. The composition of any one of claims 1 to 22, wherein the bromine-containing marker comprises at least one compound having the formula-J^N-C(O)-NH-NH₂The label of imide group of (A) wherein J is^NIs a bond, an ester oxygen-O-group, or an amine-NH-group, and is selected from the group consisting of:

-(B-6-i)

wherein n is_YMIs an integer of 1 to 4, Ar^YMIs an aromatic group;

-(B-6-ii)

wherein n is_YMIs an integer of 1 to 4, Ar^YMIs an aromatic group;

-(B-6-iii)

wherein n is_YMIs an integer of 1 to 4, Ar^YMIs aromaticA group.

35. The composition of claim 34, wherein in formula (B-6-i), Ar^YMIs fluorinated.

36. The composition of claim 34, wherein in formula (B-6-ii), Ar^YMIs fluorinated.

37. The composition of claim 34, wherein in formula (B-6-iii), Ar^YMIs fluorinated.

38. The composition of any one of claims 1 to 22, wherein the fluoroelastomer comprises repeating units derived from at least one cure site-containing monomer having at least one nitrile group selected from the group consisting of:

(CS-N2) has the formula CF₂＝CF-(OCF₂CFX^CN)_m’-O-CF₂—CF(CF₃) -CN nitrile group-containing perfluorovinyl ethers of which X is^CNIs F or CF₃And m' is 0, 1, 2, 3 or 4.

39. A process for the manufacture of a shaped article comprising curing the composition of any one of claims 1 to 38.

40. A cured article obtained from the composition of any one of claims 1 to 38, which is a sealed article.

41. The cured article of claim 40, selected from the group consisting of: o or quad rings, shims, spacers, shaft seals, valve stem seals, piston rings, crankshaft seals, camshaft seals, and oil seals, pipes, and tubes.

42. A method for detecting wear/damage in the cured article of claim 40, the method comprising: monitoring the release of bromine-containing compounds resulting from said abrasion/damage.